Power Flow Simulation of Flywheel Energy Storage Systems for Tramways

Abstract

Energy storage devices, such as flywheel storages, can be used in railway systems, especially tramways, to save energy from being turned into heat in the braking resistor. This paper provides a quantitative analysis for the possible energy savings by using a flywheel energy storage system in a tramway. For this purpose a flywheel is modeled considering various internal losses. Based on the defined operating strategy, the power flow of the traction system is analyzed for a given driving cycle. The energy consumption of a tram with a flywheel system is compared to the consumption of a conventional tram without an energy storage device and a tram with a storage device based on supercaps. Finally, the influence of the grid feedin power limit on the energy savings is analyzed.

Comparison of different tram cars in Poland basing on drive type, rated power and energy consumption

“…Erd et al [12] analysed possibilities of lessening energy consumption in tram by applying flywheels (rotating energy storage devices). They used data for Variobahn tram (6 motors, 95 kW each, carrying capacity 240 passengers) provided by Bombardier company (distance 17.6 km, route in Heidelberg city).…”

Fault Tolerant Control Based SFO-Intelligent PID: Application on SynRM for Flywheel Energy Storage Systems -Part I

“…A synchronous reluctance motor/generator with low cost, high efficiency, and low rotor weight is designed. Such conventional flywheels operating at speeds up to 6000 rev/min, together with suitable power converters (drives), electrical motor/generators, and controllers, offer a number of benefits [3][4][5][6]:…”

“…The flywheels in recent years, with the help of modern power electronics and high strength materials, high performance flywheels are further developed, different from the earlier times where it were constructed with steel, which had large dimensions and big masses. However, the discussion about the application of this technology is still ongoing concerning their costs, energy density and complexity [3][4][5][6].…”